Boolean - subtract multiple objects from one with only one boolean modifier
No, you can't input multiple objects into a single boolean modifier.

You can add as many boolean modifiers as you want though. Simply create multiple boolean modifiers with their respective object's input.

You can also join all objects into a single object and use that as the boolean input. E.g. you could duplicate your window, then merge it into the boolean input object by &#8679; Shift RMB selecting the input object (making it active) and pressing &#9096; CtrlJ to join them.

As you intend to speed up the process, I'd advise you to use the built-in BoolTools addon, which creates a shelf for assign boolean quickly.